SHEAR STRENGTH OF SEISMIC RETROFITED R/C FRAMES WITHOUT ANCHOR BOLTS

Behavior of the frames with R/C wall and effects of frictions at the frame-wall joints

Abstract

Being insufficient seismic capacities of the existing buildings not designed in accordance with the current code, it is politically encouraged to improve their structural properties which are specified stiffness, strength and ductility. Conventionally, bare frames of the buildings are strengthened using of steel braces or shear walls and connected by the use of many dowel anchor bolts and grouting mortar. To develop new strengthening methods without the anchor bolts, we performed a series of cyclic loading tests of R/C framed specimens retrofitted with shear walls built with cast-in-place concrete.
Two specimens exhibited high shear capacities with no less than three times of the bare frames. By taking the friction at the frame-wall joint into account, a means to evaluate the shear capacities based on the proposed resisting mechanism was presented.